The Roman Calendar Home Calendar The Roman Calendar The Roman Calendar The ancient Roman calendar, or “pre-Julian” calendar, is believed to have been a lunar calendar. The calendar originally consisted of hollow months that were 29 days long or full months that had 30 days. The Colosseum in Rome. The Colosseum in Rome is one of the most famous ruins from the Roman era. ©iStockphoto.com/matthewleesdixon King Romulus The original Roman calendar was said to be invented by Romulus, the first king of Rome, around 753 BCE . The calendar started the year in March (Martius) and consisted of 10 months, with 6 months of 30 days and 4 months of 31 days. The winter season was not assigned to any month, so the calendar year only lasted 304 days with 61 days unaccounted for in the winter. Calendar of Romulus: December - 30 Days Calends, Nones, and Ides Unlike the Julian and Gregorian calendars, the Roman calendar had a different system for numbering the days of the month.

The months were divided into day markers that fell at the start of the month, the fifth or seventh day, and in the middle of the month. These 3 markers were called Calends, Nones and Ides. Calends (Kalendae, Kalends) signify the start of the new moon cycle and was always the first day of the month. It is derived from the Greek word καλειν, “to announce” the days of the full and new moon. Nones (Nonae) were known to be the days of the half moon which usually occur 8 days before the Ides. Ides occurred on the 15th day of March, May, July, and October, and the 13th day of the other months. They are thought to have been the days of the full moon. Each day was referred to by how many days it fell before the Calends, Nones or Ides. For example, March 11 would be known as “Five Ides” to the Romans because it is four days before the Ides of March (March 15). Adding January and February The 304-day Roman calendar didn’t work for long because it didn’t align with the seasons.

King Numa Pompilius reformed the calendar around 700 BCE by adding the months of January (Ianuarius) and February (Februarius) to the original 10 months, which increased the year's length to 354 or 355 days. The addition of January and February meant that some of the months' names no longer agreed with their position in the calendar (September - December). The month Quintilis was renamed July in honor of Julius Caesar in 44 BCE and Sextilis was renamed August in honor of Augustus in 8 BCE. The Intercalary Month The Roman calendar was still flawed after adding January and February, as well as the days and months needed to keep the calendar in line with the seasons. Many attempts were made to align the calendar with the seasons but all failed. An extra month was added to the calendar in some years to make up for the lack of days in a year. The insertion of the intercalary month was made by the pontifex maximus, the high priest of the College of Pontiffs in ancient Rome.

However this system was flawed because the Roman calendar year defined the term of office of elected officials, thus a pontifex maximus could control the length of the year depending on their political agenda. When Julius Caesar became pontifex maximus, he reformed the calendar by getting rid of the intercalary months. The Julian calendar was created, then completed during his successor Augustus' reign. Roman Calendar Months January – first month of the year Saxon - Wulf-monath - wolf month History of January The month of January was added to the Roman calendar by Numa Pompilius around 700 BCE so that the calendar would equal a standard lunar year of 355 days. January became the first month of the year around 450 BCE, although March was originally the first month of the year in the old Roman calendar. January originally consisted of 30 days when it was added to the 10-month Roman calendar. However, a day was added making it 31 days long in 46 BCE by Julius Caesar. First Month in the Year January is the first month of the year in the Julian and Gregorian calendar that consists of 31 days.

It did not exist in the 10-month Roman calendar. It is considered the coldest month of the year in most of the Northern Hemisphere and the warmest month of the year in most of the Southern Hemisphere. January starts on the same day of the week as October and ends on the same day of the week as February and October in common years. During leap years , January starts on the same day of the week as April and July, and ends on the same day of the week as July. Birth Flower and Stone January's birth flower is the Dianthus caryophyllus or Galanthus. The birthstone for January is the garnet which symbolizes constancy. Gregorian Months - True Lunar Gregorian Months Gregorian Months TrueLunar 2016-03-17T05:37:39+00:00 Numa Pompilius Gregorian Months The Gregorian Calendar (a solar calendar) was instituted in 1582 A.D. by Pope Gregory XIII as a reform to the Julian Calendar, which was instituted in 46 B.C. by Julius Caesar.

However, the title Gregorian Months is a bit misleading; however, I felt that this title was appropriate for identification purposes, due to its familiarity. Nevertheless, the origination of the names of the months in our current calendar goes far beyond Pope Gregory, or even Julius Caesar. Roman legend attributes the discovery of the Roman civilization to Romulus, its first king (one of two brother who were apparently raised by wolves) who was also responsible for instituting their calendar. However, this calendar only consisted of ten “named” months (March through December), and the remaining two months of winter were simply disregarded. It wasn’t until around 753 BC when Numa Pompilius , Rome’s second king, that the two disregarded months were given names, hence the birthing of January and February. Though it appears that the names of the Roman months (aside from January and February) were accredited to Romulus , his actual existence (and seemingly his contributions) has been quite difficult to substantiate, hence earning the classification of “legendary.” With that being the case, I felt that it would appropriate and fitting to focus on and discuss Numa’s contribution.

Also, please keep in mind that the months July (the fifth month) and August (the sixth month) were originally named Quintilis and Sextilis, respectively, and were renamed in honor of Julius Caesar (in 44 BC) and his great-nephew Caesar Augustus (between 26 – 23 BC) under the Julian Reform . JANUARY The Galileo Project | Chronology | Gregorian Calendar The Galileo Project > Chronology > Gregorian Calendar The Gregorian Calendar How do we keep track of time? When do we plant our crops, how do we know when to observe religious holidays? Societies need some way to keep track of time, and complex calendars (the word comes from the Roman term for the beginning of the month) were developed early in human history. In agricultural societies the seasonal cycle of the Sun is crucial, but for shorter periods the lunar cycle suggests itself as well. Historically the problem was that the year does not contain a whole number of days or months.

The mean interval between successive vernal equinoxes (365.2424 days), is about 11 minutes less than 365 1/4 days; the synodic period of the Moon (the time between successive full moons or new moons) is about 29 1/2 days, and thus 12 months add up to about 354 days. Constructing a calendar that incorporates both the movements of the Sun and Moon is therefore not a simple business. Various solutions have been tried. The Egyptian calendar was perhaps the simplest solution. The year was made up of twelve months of thirty days each, and five days were added at the end. Since this meant an error of about 1/4 day per year, the starting date of the year slowly drifted forward with respect to the seasons until after 1460 years it had returned to where it started. The rising of the Nile, the crucial event in the Egyptian agricultural cycle, was predicted by the heliacal rising of Sirius,[ 1 ] the brightest star in the heavens. No attention was paid to the Moon.

Most cultures in the ancient Near East relied on a calendar in which months had alternating lengths of 29 and 30 days and added a month about every third year. Thus, in ancient Israel the elders added an extra month of 29 days every third year after the sixth month (Adar). But these 29 days would not make up entirely for the entire deficit of 3 x 11 1/4 days, and therefore in some years two extra months had to be added. In the Greek city states months were added haphazardly as needed and no consistent system of intercalation was ever developed. The most sophisticated system of keeping the motions of both the Sun and Moon harnessed in a single calendar was developed in Mesopotamia. By the Persian period, ca. 500, the system incorporated the so-called Metonic cycle (we name it after the Greek Meton, ca. 425 BCE) in which the following relationship is used: 19 solar years contain 6939 3/4 days; 110 months of 29 days plus 125 months of 30 days add up to 6940 days.

19 years, then, contained 235 months, and starting in (on our calendar) 499 BC, the calendar in that part of the world was regulated on a cycle of intercalating 7 extra months in 19 years, as shown in the following scheme (in which a dash indicates a year of 12 months and a VI or XII indicated a year in which a month was added after the sixth or twelfth month): - - XII - - XII - XII - - XII - - XII - - VI - XII After a few irregularities, starting in 384 BCE, this scheme was rigorously adhered to, through the Greek and Roman conquests, until 75 CE, when cuneiform texts ceased. For convenience, the month was usually subdivided into smaller time periods. The Greeks divided the month into three periods of ten days, but a division of seven days was older and more common in the Near East. We find the seven-day week already in Genesis. The names that we assign to the days have their origin in the division of the day into 24 hours, which originated in Egypt.

In the Hellenistic period (300 BCE - 100 BCE) it became common to assign a ruling planet (including the Sun and Moon) to each hour of the day. The common order of the wandering heavenly bodies was Saturn-Jupiter-Mars-Sun-Venus-Mercury-Moon. The first hour of the first day was assigned to the Sun, the second to Venus, the third to Mercury, etc., repeating the cycle in the order given above. The 24th hour was thus assigned to Mercury and the first hour of the second day to the Moon. Naming the days after the planets that rule their first hours, we thus arrive at the sequence Sun's day-Moon's day-Mars's day-Mercury's day-Jupiter's day-Venus's day-Saturn's day.[ 2 ] The modern English variations on these names are due to substituting Nordic or Saxon gods for some of the Roman names: Tiw for Mars, Wotan for Mercury, Thor for Jupiter, Frigg for Venus. Our civil method for reckoning time, then has a mixed origin.

Our division of the hour into minutes and seconds is derived from the sexagesimal system of the Mesopotamians; the division of the day into 24 hours originated with the Egyptians; the seven-day week originated in the ancient Near East, while the names are derived from a Greek convention developed during the Hellenistic period. Our calendar is based on the motion of the Sun alone, but our various religious calendars are based on a combination of the motions of the Sun and Moon. Our civil calendar derives from the Romans with some alterations. Its origin is described nicely in the "Calendar" article in the 11th edition of the Encyclopedia Britannica (1910), which reads in part: The civil calendar of all European [and American] countries has been borrowed from that of the Romans. Romulus[ 3 ] is said to have divided the year into ten months only, including in all 304 days, and it is not very well known how the remaining days were disposed of. The ancient Roman year commenced with March, as is indicated by the names September, October, November, December, which the last four months still retain.

July and August, likewise, were anciently denominated Quintillis and Sextillis, their present appellations having been bestowed in compliment to Julius Caesar and Augustus. In the reign of Numa[ 4 ] two months were added to the year, January at the beginning and February at the end; and this arrangement continued till the year 452 BC., when the Decemvirs[ 5 ] changed the order of the months, and placed February after January. The months now consisted of twenty-nine and thirty days alternately, to correspond with the synodic revolution of the moon [full moon to full moon], so that the year contained 354 days; but a day was added to make the number odd, which was considered more fortunate, and the year therefore consisted of 355 days.

This differed from the solar year by ten whole days and a fraction; but to restore the coincidence, Numa ordered an additional or intercalary month to be inserted every second year between the 23d and 24th of February, consisting of twenty-two and twenty-three days alternately, so that four years constituted 1465 days, and the mean length of the year was consequently 366 1/4 days. The additional month was called Mercedinus or Mercedonius, from merces, wages, probably because the wages of workmen and domestics were usually paid at this season of the year. According to the above arrangement, the year was too long by one day, which rendered another correction necessary. As the error amounted to twenty-four days in as many years, it was ordered that every third period of eight years, instead of containing four intercalary months, amounting in all to ninety days, should contain only three of those months, consisting of twenty-two days each.

The mean length of the year was thus reduced to 365 1/4 days; but it is not certain at what time the octennial periods, borrowed from the Greeks, were introduced into the Roman calendar, or whether they were at any time strictly followed. It does not even appear that the length of the intercalary month was regulated by any certain principle, for a discretionary power was left with the pontiffs,[ 6 ] to whom the care of the calendar was committed, to intercalate more or fewer days according as the year was found to differ more or less from the celestial motions. This power was quickly abused to serve political objects, and the calendar consequently thrown into confusion. By giving a greater of less number of days to the intercalary month, the pontiffs were enabled to prolong the term of a magistracy or hasten the annual elections; and so little care had been taken to regulate the year, that, at the time of Julius Caesar, the civil equinox differed from the astronomical by three months, so that the winter months were carried back into autumn and the autumnal into summer.

In order to put an end to the disorders arising from the negligence or ignorance of the pontiffs, [Julius] Caesar abolished the use of the lunar year and the intercalary month, and regulated the civil year entirely by the sun. With the advice and assistance of Sosigenes,[ 7 ] he fixed the mean length of the year at 365 1/4 days, and decreed that every fourth year should have 366 days, the other years having each 365. In order to restore the vernal equinox to the 25th of March, the place it occupied in the time of Numa, he ordered two extraordinary months to be inserted between November and December in the current year, the first to consist of thirty three, and the second of thirty-four days. The intercalary month of twenty-three days fell into the year of course, so that the ancient year of 355 days received an augmentation of ninety days; and the year on that occasion contained in all 445 days. This was called the last year of confusion.

The first Julian year commenced with the 1st of January of the 46th before the birth of Christ, and the 708th from the foundation of the city. In the distribution of the days through the several months, Caesar adopted a simpler and more commodious arrangement than that which has since prevailed. He had ordered that the first, third, fifth, seventh, ninth, and eleventh months, that is January, March, May, July, September and November, should have each thirty-one days, and the other months thirty, excepting February, which in common years should have only twenty-nine day, but every fourth year thirty days. This order was interrupted to gratify the vanity of Augustus, by giving the month bearing his name as many days as July, which was named after the first Caesar. A day was accordingly taken from February and given to August; and in order that three months of thirty-one days might not come together, September and November were reduced to thirty days, and thirty-one given to October and December. For so frivolous a reason was the regulation of Caesar abandoned, and a capricious arrangement introduced, which it requires some attention to remember.

[ 8 ] The additional day which occurred every fourth year was given to February, as being the shortest month, and was inserted in the calendar between the 24th and 25th day. February having then twenty-nine days, the 25th was the 6th of the calends of March, sexto calendas; the preceding, which was the additional or intercalary day, was called bis-sexto calendas,--hence the term bissextile, which is still employed to distinguish the year of 366 days. The English denomination of leap year would have been more appropriate if that year had differed from common years in defect, and contained only 364 days. In the modern calendar the intercalary day is still added to February, not, however, between the 24th and 25th, but as the 29th. . . .

Although the Julian method of intercalation is perhaps the most convenient that could be adopted, yet, as it supposes the year too long by 11 minutes 14 seconds, it could not without correction very long answer the purpose for which it was devised, namely, that of preserving always the same interval of time between the commencement of the year and the equinox. Sosigenes could scarcely fail to know that this year was too long; for it had been shown long before, by the observations of Hipparchus [ca. 125 BCE], that the excess of 3651/4 days above a true solar year would amount to a day in 300 years. The real error is indeed more than double of this, and amounts to a day in 128 years; but in the time of Caesar the length of the year was an astronomical element not very well determined. In the course of a few centuries, however, the equinox sensibly retrograded towards the beginning of the year. When the Julian calendar was introduced, the equinox fell on the 25th of March.

At the time of the Council of Nicea, which was held in 325, it fell on the 21st . . . . The Julian Calendar was naturally adopted by the successor of the Roman Empire, Christian Europe with the Papacy at its head. By about 700 CE it had become customary to count years from the starting point of the birth of Christ (later corrected by Johannes Kepler to 4 BCE). But the equinox kept slipping backwards on the calendar one full day every 130 years. By 1500 the vernal equinox fell on the 10th or 11th of March and the autumnal equinox on the 13th or 14th of September, and the situation was increasingly seen as a scandal. The most important feast day on the Christian calendar is Easter, when the suffering, death, and resurrection of Christ are celebrated. In the New Testament we find that Christ's crucifixion occurred in the week of Passover. On the Jewish calendar, Passover was celebrated at the full moon of the first month (Nissan) of spring.

In developing their own calendar (4th century CE), Christians put Easter on the first Sunday after the first full moon after the spring equinox. If the equinox was wrong, then Easter was celebrated on the wrong day. Most other Christian observances (e.g., the beginning of Lent, Pentecost) are reckoned backward or forward from the date of Easter. An error in the equinox thus introduced numerous errors in the entire religious calendar. Something had to be done. After the unification of the Papacy in Rome, in the fifteenth century, Popes began to consider calendar reform. After several false starts, a commission under the leadership of the Jesuit mathematician and astronomer Christoph Clavius (1537-1612) succeeded. Several technical changes were instituted having to do with the calculation of Easter, but the main change was simple. In 1582 Pope Gregory XIII (hence the name Gregorian Calendar) ordered ten days to be dropped from October, thus restoring the vernalequinox at least to an average of the 20th of March, close to what it had been at the time of the Council of Nicea.

In order to correct for the loss of one day every 130 years, the new calendar dropped three leap years every 400 years. Henceforth century years were leap years only if divisible by 400. 1600 and 2000 are leap years; 1700, 1800 and 1900 are not. The new calendar, although controversial among technical astronomers, was promulgated from Rome and adopted immediately in Catholic countries. Protestant countries followed suit more slowly. Protestant regions in Germany, and the northern Netherlands adopted the calendar within decades. The English, always suspicious of Rome during this period, retained the Julian Calendar. Further, while others now began the new year uniformly on 1 January, the English began it on 25 March (an older custom). Now, for example, the date 11 February 1672 in England was 21 February 1673 on the Continent. After 1700 in which the Julian Calendar had a leap year but the Gregorian did not, the difference was eleven days.

The English and their American colonies finally adopted the Gregorian Calendar in the middle of the eighteenth century. George Washington was born on 11 February on the Julian Calendar; we celebrate his birthday on 22 February. Note, finally, that the Gregorian Calendar is useless for astronomy because it has a ten-day hiatus in it. For the purpose of calculating positions backward in time, astronomers use the Julian Date. Notes [1 ]The time of year when Sirius comes out of the rays of the Sun and is first visible on the eastern horizon at sunrise. [2 ]See Otto Neugebauer, The Exact Science in Antiquity, 2d ed. (Providence: Brown University Press, 1957), pp. 82-86. [3 ]Legendary founder and first king of Rome, ca. 750 BC. [4 ]Numa Pompilius, second legendary king of Rome, ca. 700 BC. [5 ]Decemviri: any college of ten magistrates in ancient Rome.

The most famous college was the decemviri legibus scribendis, or the "composers of the Twelve Tables," who ruled Rome absolutely for a few years around 450 BC. [6 ]Roman high priests. [7 ]A Greek astronomer and mathematician who flourished in the first century BC None of his writings have survived and we know about him only through the writings of Pliny (d. 79 AD). Pliny tells us that Sosigenes was consulted by Julius Caesar about the calendar (Natural Histories, xviii, 25). [8 ]Thirty days has September, April, June, and November . . . Source Gregorian Reform of the Calendar: Proceedings of the Vatican Conference to Commemorate its 400th Anniversary, 1582-1992, ed. G. V. Coyne, M. A. Hoskin, and O. Pedersen (Vatican City: Pontifical Academy of Sciences, Specolo Vaticano, 1983).

Jean Meeus and Denis Savoie, "The history of the tropical year," Journal of the British Astronomical Association, 102 #1 (1992): 40-42 History Of Our Calendar | Calendars Why does February have only 28 days? Has the year always started on 1 January? In some ways, yes. When Julius Caesar introduced his calendar in 45 B.C.E., he made 1 January the start of the year, and it was always the date on which the Solar Number and the Golden Number were incremented. However, the church didn’t like the wild parties that took place at the start of the new year, and in C.E. 567 the council of Tours declared that having the year start on 1 January was an ancient mistake that should be abolished. Through the middle ages various New Year dates were used.

If an ancient document refers to year X, it may mean any of 7 different periods in our present system: 1 Mar X to 28/29 Feb X+1 1 Jan X to 31 Dec X 1 Jan X-1 to 31 Dec X-1 25 Mar X-1 to 24 Mar X 25 Mar X to 24 Mar X+1 Saturday before Easter X to Friday before Easter X+1 25 Dec X-1 to 24 Dec X Choosing the right interpretation of a year number is difficult, so much more as one country might use different systems for religious and civil needs. The Byzantine Empire used a year starting on 1 Sep, but they didn’t count years since the birth of Christ, instead they counted years since the creation of the world which they dated to 1 September 5509 B.C.E. Since about 1600 most countries have used 1 January as the first day of the year. Italy and England, however, did not make 1 January official until around 1750.

In England (but not Scotland) three different years were used: The historical year, which started on 1 January. The liturgical year, which started on the first Sunday in advent. The civil year, which → See the British Calendar Act of 1751 . It is sometimes claimed that having the year start on 1 January was part of the Gregorian calendar reform. This is not true. This myth has probably started because in 1752 England moved the start of the year to 1 January and also changed to the Gregorian calendar. But in most other countries the two events were not related. Scotland, for example, changed to the Gregorian calendar together with England in 1752, but they moved the start of the year to 1 January in 1600. Then what about leap years? If the year started on, for example, 1 March, two months later than our present year, when was the leap day inserted? When it comes to determining if a year is a leap year, since AD 8 the Julian calendar has always had 48 months between two leap days.

So, in a country using a year starting on 1 March, 1439 would have been a leap year, because their February 1439 would correspond to February 1440 in the January-based reckoning. What is the origin of the names of the months? A lot of languages, including English, use month names based on Latin. Their meaning is listed below. However, some languages (Czech and Polish, for example) use quite different names. Month From the word decem, ten, because it was the 10th month in the old Roman calendar. How did Dionysius date Christ’s birth? There are quite a few theories about this. And many of the theories are presented as if they were indisputable historical fact. The following are two theories that tend to be more accepted: According to the Gospel of Luke (3:1 & 3:23) Jesus was "about thirty years old" shortly after "the fifteenth year of the reign of Tiberius Caesar." Tiberius became emperor in C.E. 14. If you combine these numbers you reach a birthyear for Jesus that is strikingly close to the beginning of our year reckoning.

This may have been the basis for Dionysius’ calculations. Dionysius’ original task was to calculate an Easter table. In the Julian calendar, the dates for Easter repeat every 532 years. The first year in Dionysius’ Easter tables is C.E. 532. Is it a coincidence that the number 532 appears twice here? Or did Dionysius perhaps fix Jesus’ birthyear so that his own Easter tables would start exactly at the beginning of the second Easter cycle after Jesus’ birth? Was Jesus born in the year 0? No. There are two reasons for this: There is no year 0. Jesus was born before 4 B.C.E. The concept of a year "zero" is a modern myth (but a very popular one). In our calendar, C.E. 1 follows immediately after 1 B.C.E. with no intervening year zero. So a person who was born in 10 B.C.E. and died in C.E. 10, would have died at the age of 19, not 20.

Furthermore, as described in section 2.14, our year reckoning was established by Dionysius Exiguus in the 6th century. Dionysius let the year C.E. 1 start one week after what he believed to be Jesus’ birthday. But Dionysius’ calculations were wrong. The Gospel of Matthew tells us that Jesus was born under the reign of king Herod the Great, who died in 4 B.C.E.. It is likely that Jesus was actually born around 7 B.C.E.. The date of his birth is unknown; it may or may not be 25 December. Why do the 9th thru 12th months have names that mean 7th, 8th, 9th and 10th? September through December were the seventh through tenth months of a calendar used by the first Romans. Ancient historian and Greek biographer Plutarch, wrote in C.E. 75, about how they became displaced to two positions higher than their names would indicate. → Read more about the early Roman calendar. Why does February have only 28 days? January and February both date from about the time of Rome’s founding.

They were added to a calendar that had been divided into ten month-like periods whose lengths varied from 20 to 35 or more days. A winter season was not included, so those period lengths are believed to have been intended to reflect growth stages of crops and cattle. When introduced, January was given 29 days and put at the beginning of the calendar year. February was given 23 days and put at the end. Then, for an undetermined period shortly after Rome’s founding, months were said to have begun when a new moon was first sighted. At some later time, month lengths were separated from lunations and again became fixed. At that time, February’s original length was extended by five days which gave it a total of 28. The Roman calendar The Roman calendar (Please include the word “calendar” in the subject line) The Roman calendar What is the Roman calendar? The Roman calendar provides the historical background for the Christian calendar. To a large extent the structure the calendar we use today is similar to the structure of the ancient Roman calendar. Before 45 BC, the Roman calendar was a mess, and much of our so-called “knowledge” about it seems to be little more than guesswork.

Originally, the year started on 1 March and consisted of only 304 days or 10 months (Martius, Aprilis, Maius, Junius, Quintilis, Sextilis, September, October, November, and December). These 304 days were followed by an unnamed and unnumbered winter period. The Roman king Numa Pompilius (c. 715-673 BC, although his historicity is disputed) allegedly introduced February and January (in that order) between December and March, increasing the length of the year to 354 or 355 days. In 450 BC, February was moved to its current position between January and March. In order to make up for the lack of days in a year, an extra month, Intercalaris or Mercedonius, (allegedly with 22 or 23 days though some authorities dispute this) was introduced in some years.

In an 8 year period the length of the years were: 1: 12 months or 355 days 8: 13 months or 378 days A total of 2930 days corresponding to an average of 366¼ days per year. This year was discovered to be too long, and therefore 7 days were later dropped from the 8th year, yielding 365.375 days per year. This is all theory. In practice it was the duty of the priesthood to keep track of the calendars, but they failed miserably, partly due to ignorance, partly because they were bribed to make certain years long and other years short. Furthermore, leap years were considered unlucky and were therefore avoided in time of crisis, such as the Second Punic War. In order to clean up this mess, a calendar reform was required. In 45 BC Julius Caesar introduced the so-called Julian calendar , but before the reformed calendar could be used, drastic measures were required to make up for the many omitted leap months.

Therefore 46 BC became a year with 15 months and 445 days; that year has been aptly termed “the last year of confusion”. The table below shows an educated guess about the length of the months in the years 47 BC (which was a typical Roman year) and 46 BC (which was anything but typical). 47 BC 355 445 The names of the two extra months between November and December are not known. It has been suggested that their names were Undecember and Duodecember, but that is doubtful, as this would mean that the names of the last four months were derived from the Latin words for nine, eleven, twelve, ten – in that order. The length of the months from 45 BC onward were the same as the ones we know today. Occasionally one reads the following story: “Julius Caesar made all odd numbered months 31 days long, and all even numbered months 30 days long (with February having 29 days in non-leap years).

In 44 BC Quintilis was renamed ‘Julius’ (July) in honour of Julius Caesar, and in 8 BC Sextilis became ‘Augustus’ in honour of emperor Augustus. When Augustus had a month named after him, he wanted his month to be a full 31 days long, so he removed a day from February and shifted the length of the other months so that August would have 31 days.” This story, however, has no basis in actual fact. It is a fabrication, possibly invented by the English-French scholar Johannes de Sacrobosco in the 13th century. [1] The Romans didn’t number the days sequentially from 1. Instead they had three fixed points in each month: “Kalendae” (or “Calendae”), which was the first day of the month. “Idus”, which was the 13th day of January, February, April, June, August, September, November, and December, or the 15th day of March, May, July, or October. “Nonae”, which was the 9th day before Idus (counting Idus itself as the 1st day).

The days between Kalendae and Nonae were called “the 5th day before Nonae”, “the 4th day before Nonae”, “the 3rd day before Nonae”, and “the day before Nonae”. (There was no “2nd day before Nonae”. This was because of the inclusive way of counting used by the Romans: To them, Nonae itself was the first day, and thus “the 2nd day before” and “the day before” would mean the same thing.) Similarly, the days between Nonae and Idus were called “the Xth day before Idus”, and the days after Idus were called “the Xth day before Kalendae (of the next month)”. Julius Caesar decreed that in leap years the “6th day before Kalendae of March” should be doubled. So in contrast to our present system, in which we introduce an extra date (29 February), the Romans had the same date twice in leap years. The doubling of the 6th day before Kalendae of March is the origin of the word bissextile.

If we create a list of equivalences between the Roman days and our current days of February in a leap year, we get the following: Roman date Early Roman Calendar | Calendars Beware the Ides of March! Roman Fasti Some 200 fragments of Roman calendars have been found so far, and they are collectively known as Fasti. What did a Roman calendar look like? The Roman calendar used a system of months, and special days in each month. Some calendars were carved in marble or stone, but many were painted on walls for decoration. Different geographical areas often held different gods in special esteem, and this led to regional variations in calendars. This doesn’t seem so strange when one considers that even within the US, Mardi Gras often appears only on Southern calendars, and Lincoln’s birthday sometimes does not. In 45 B.C.E., Romans modified their method of marking time to keep it in phase with seasons, but not require intercalation of an extra month. They accomplished this with the Julian Calendar. Month lengths were extended to bring the calendar’s total to 365 days, making it truly solar.

This change was accompanied by addition of an extra day every fourth year (after February 23rd) because of the almost six extra hours beyond 365 days in a tropical year. How do you read the calendar? In the calendar of the ancient Romans, the months contained three primary markers  the Kalends, the Nones and the Ides. The Kalends were always the first day of the month. The Nones were usually the 5th but sometimes the 7th, and the Ides were the 15th but sometimes the 13th. All the days after the Ides were numbered by counting down towards the next month’s Kalends. The holidays were generally bunched together to form continuous celebrations, and the remaining days of the month were usually nondescript workdays. The days were each identified with certain letters and names. The Kalends were always identified as shown in the diagram at right. The archaic form of the K, for Kalends, was used in front of the name of the month. The first letter was called the Nundinae ("nine day") , or the Nundinal letter, and it represented the market day.

Every 9th day (counting inclusively) was a market day, but as it shifted every year, a designated letter between A and H would represent the market day for that year. The final letter identifies the type of day for purposes of religious observance or legal business. The top diagram shows a typical non-holiday. The first letter is the nundinal letter for the market day. If the market day for this year was E then this would be a market day. The second letter signifies the type of religious or legal observance required or permitted on this day. In this case the letter C represents dies comitiales, days when committees of citizens could vote on political or criminal matters. The other letter designations : F stands for dies fasti, days on which legal action is permitted. N stands for dies nefasti, which meant that no legal action or public voting could take place on this day. EN stands for endotercisus, or intercisus, which were "in-between" F or C days in which mornings and afternoons had different designations. NP, the combination of N and P, represented some important type of religious observance of which all records have disappeared.

However, they all seem to be directly associated with major holidays. FP also represented some religious holiday, but no definition survives for this abbreviation. The center diagram is a typical festival, or feriae. On these days the day letter follows the holiday name, which is abbreviated in these calendars. These holidays are explained in the write-up for each day. The Romans enjoyed more holidays than the number of our holidays and weekends combined. Roman taxes were also only a tithe, or 10%. One of the hallmarks of progress seems to be that the populace is always made to work longer and, on top of it all, they are taxed more. What were the Roman weekdays? The Romans did not have weekdays in the same sense as our Monday, Tuesday, etc., however, they did have a defined markers within each month. Originally, the month and the markers were based on the moon. At the time of their early kings, Roman months were of a length identical to the lunar cycle. Each month was divided into sections that ended on the day of one of the first three phases of the moon: new, first quarter or full. All days were referred to in terms of one of these three moon phase names, Kalends, Nones or Ides.

At that time a pontifex (priest) was assigned to observe the sky. When he first sighted a thin lunar crescent he called out that there was a new moon and declared the next month had started. For centuries afterward, Romans referred to the first day of each month as Kalendae or Kalends from the Latin word calare (to announce solemnly, to call out). The word calendar was derived from this custom. Day of Kalends Of the three sections, Kalends was the longest  it had more days than the other two combined. That’s because it spanned more than two lunar phases, starting from the day after full moon and continuing thru its last quarter and waning period, then past the dark new moon until another lunar crescent was sighted. The day of Kalends itself began a new month. It was dedicated to Juno, a principal goddess of the Roman Pantheon. Unnamed days in the early Roman month were assigned a number by counting down following the day of each named phase, day by day, ending with the next of those three phases. The first numbered day in each section had the section’s highest value. Each succeeding day was one number lower than that of the day before.

(Similar to the modern count-down when coordination of a group of people is required for a complicated activity such as launching a rocket.) Latin for "the evening before" is "Pridie," a word that was used to refer to the day before each of these named phases. So Pridie was always the day that would otherwise have been numbered two. The count-down was inclusive; the day from which they started as well as that of the moon phase to which they were counting down, day one, were both included. Day of Nones Nones (Latin nonus or ninth) was originally the day when the moon reached its first quarter phase. When the pontifex initially saw the lunar crescent he noted its width and, using empirical knowledge, calculated the number of days that were expected to elapse between then and the first quarter moon. He then specified that number after he announced the new crescent. If he called out the number six, the day following Kalends would be referred to as the sixth day before Nones. In any given year, the second day of Martius might well have been designated as the sixth of the Nones of March: "ante diem VI Non.

Mart." If this were the case, Nones would be the seventh day and Ides would be the 15th day of that month. The difference between these two dates, eight days, was always the length of the Ides section. Use of the word "Nones" (nine) was intended to express the inclusive number of elapsed days between first quarter and full moons. Actually, the time between moon phases now averages about 7.4 days, but they sometimes occur eight days apart. Eight-day separations of first quarter and full moons now usually come grouped in consecutive lunations. They then give way to mostly seven-day periods. Six of the first seven lunations of 1997, for instance, had their first quarter and full moon phases eight days apart (inclusive nine-day spans). Also, July 1 of 1998 had a first-quarter moon followed by a new moon on July 9, a nine-day period. This helps explain why the unlikely term of Nones, meaning ninth, was used to designate one fourth of the moon’s period that now averages about 29.53 days. Day of Ides Ides, dedicated to Jupiter, was originally the time of the full moon.

Because a full moon comes halfway thru each lunation, its day was called Idus in Latin from an Etruscan word meaning "divide." After Ides, the next new moon was expected to appear in from 15 to 17 days. Variations in the length of time before another new moon can be sighted is due to constantly changing positions of moon and Earth relative to the sun. When did they stop using the moon for months? Romans separated their months from the lunar cycle in the fifth century B.C.E. Month lengths then became fixed. At that time, Ides was assigned as the 15th day in all months given 31 days in length  March, May, July and October. It was designated as the 13th day in all other months. As a result, from then on the Kalends section had from 16 to 19 days, the Nones section had either four or six days and the Ides section, as before, always had eight days.

Sometime after Kalends, Nones and Ides were fixed on predetermined days of the month rather than being defined by phases of the moon, Romans used letters A thru H on the left side of each month’s calendar column to indicate days of their eight-day marketing week. The first day of each new year was represented by the letter "A." When did the early Roman calendar begin? The early Roman calendar originated as a local calendar in the city of Rome, supposedly drawn up by Romulus some seven or eight centuries before the Christian Era. The year began in March and consisted of 10 months, six of 30 days and four of 31 days, making a total of 304 days: it ended in December, to be followed by what seems to have been an uncounted winter gap. Numa Pompilius, according to tradition the second king of Rome (715?-673? B.C.E.), is supposed to have added two extra months, January and February, to fill the gap and to have increased the total number of days by 50, making 354.

To obtain sufficient days for his new months, he is then said to have deducted one day from the 30-day months, thus having 56 days to divide between January and February. But since the Romans had, or had developed, a superstitious dread of even numbers, January was given an extra day; February was still left with an even number of days, but as that month was given over to the infernal gods, this was considered appropriate. The system allowed the year of 12 months to have 355 days, an uneven number. When did the Roman republican calendar begin? The so-called Roman republican calendar was supposedly introduced by the Etruscan Tarquinius Priscus (616-579 B.C.E.), according to tradition the fifth king of Rome. The Roman republican calendar was a dating system that evolved in Rome prior to the Christian era. According to legend, Romulus, the founder of Rome, instituted the calendar in about 738 B.C.E. This dating system, however, was probably a product of evolution from the Greek lunar calendar, which in turn was derived from the Babylonian.

The original Roman calendar appears to have consisted only of 10 months and of a year of 304 days. The remaining 61¼ days were apparently ignored, resulting in a gap during the winter season. The months bore the names Martius, Aprilis, Maius, Juniius, Quintilis, Sextilis, September, October, November, and Decemberthe last six names correspond to the Latin words for the numbers 5 through 10. The Roman ruler Numa Pompilius is credited with adding January at the beginning and February at the end of the calendar to create the 12-month year. In 452 B.C.E., February was moved between January and March. By the 1st century B.C.E., the Roman calendar had become hopelessly confused. The year, based on cycles and phases of the moon, totaled 355 days, about 10¼ days shorter than the solar year. The occasional intercalation of an extra month of 27 or 28 days, called Mercedonius, kept the calendar in step with the seasons. The confusion was compounded by political maneuvers.

The Pontifex Maximus and the College of Pontiffs had the authority to alter the calendar, and they sometimes did so to reduce or extend the term of a particular magistrate or other public official. Finally, in 46 B.C.E., Julius Caesar initiated a thorough reform that resulted in the establishment of a new dating system, the Julian calendar. He wanted the year to begin in January since it contained the festival of the god of gates (later the god of all beginnings), but expulsion of the Etruscan dynasty in 510 B.C.E. led to this particular reform’s being dropped. The Roman republican calendar still contained only 355 days, with February having 28 days; March, May, July, and October 31 days each; January, April, June, August, September, November, and December 29 days. It was basically a lunar calendar and short by 10¼ days of a 365¼ -day tropical year.

In order to prevent it from becoming too far out of step with the seasons, an intercalary month, Intercalans, or Mercedonius (from merces, meaning wages, since workers were paid at this time of year), was inserted between February 23 and 24. It consisted of 27 or 28 days, added once every two years, and in historical times at least, the remaining five days of February were omitted. The intercalation was therefore equivalent to an additional 22 or 23 days, so that in a four-year period the total days in the calendar amounted to (4 x 355) + 22 + 23, or 1,465: this gave an average of 366.25 days per year. Intercalation was the duty of the Pontifices, a board that assisted the chief magistrate in his sacrificial functions. The reasons for their decisions were kept secret, but, because of some negligence and a measure of ignorance and corruption, the intercalations were irregular, and seasonal chaos resulted.

In spite of this and the fact that it was over a day too long compared with the tropical year, much of the modified Roman republican calendar was carried over into the Gregorian calendar now in general use. What were the Roman months? Much of the knowledge we now have about early Roman calendars came from Ovid, a Roman born in 43 B.C.E., and from Plutarch, a Greek biographer who wrote between C.E. 105 and 115. Both of them had access to historical documents that are no longer extant. Ovid claimed that his information was "dug up in archaic calendars," so it was already ancient over two thousand years ago. We can assume that the Roman calendar was brought from their birthplace by Rome’s original citizens. Initially, it contained only ten months. It has been suggested that those month lengths reflected growth cycles of crops and cattle. When compared with the solar year, it had an uncounted winter period of approximately sixty days. Plutarch said that months at the time of Rome’s founding were of varying lengths, some as short as twenty days and others with thirty-five or more in what early Romans believed was a year of three hundred and sixty days.

Romulus, the legendary first king, was said to have made extensive changes to those month lengths, assigning twenty-nine days to some and thirty-one to others. → Read excerpt of Plutarch’s essay . March (the first month) Both Ovid and Plutarch said that Martius, originally the first month, was named after Mars, the Roman god of war. Six of the other original ten were simply numbered as Quintilis thru Decembris (fifth thru tenth) but there were already disagreements when Ovid wrote, two thousand years ago, as to the sources of names for what were originally the second thru fourth, Aprilis, Maius and Junius. These disagreements continue to the present time. April When writing about April, Ovid said "I have come to the fourth month, full of honor for you; Venus, you know both the poet and the month are yours." It was later said that "April was sacred to Venus, and her festival  the Festum Veneris and Fortuna Virilis  occurred on the first day of this month." Apparently Aprilis stems from aphrilis, corrupted from Aphrodite, a Greek name for Venus.

Jakob Grimm, a later authority, opposed this stating it may have originated from the name of a god or hero named Aper or Aprus." May Maius was said by some to be named after the goddess Maia, a daughter of Atlas, and Junius "is indirectly named after the goddess Juno, the Roman equivalent of Frigga." But Ovid suggested that names of months we now call May and June possibly refer not to sky-gods but rather to elders and young men. January (at the end of the year) There was also disagreement in Ovid’s day as to the sequence and time at which Januarius and Februarius were added to the original ten months. Januarius became part of the calendar within half a century after Rome was founded because Plutarch said that Numa, the king who followed Romulus, made it the first month of the year and made February the last. One historian assigns that action an exact date by stating that "January and February were added to an original Roman calendar of only ten months in 713 B.C.E." January was named after Janus, a sky-god who was ancient even at the time of Rome’s founding.

Ovid quoted Janus as saying "The ancients called me chaos, for a being from of old am I." After describing the world’s creation, he again quoted Janus: "It was then that I, till that time a mere ball, a shapeless lump, assumed the face and members of a god." A Lydian named Joannes identified Janus as a planet when he wrote: "Our own Philadelphia still preserves a trace of the ancient belief. On the first day of the month there goes in procession no less a personage than Janus himself, dressed up in a two-faced mask, and people call him Saturnus, identifying him with Kronos." Early Romans believed that the beginning of each day, month and year were sacred to Janus. They thought he opened the gates of heaven at dawn to let out the morning, and that he closed them at dusk. This eventually led to his worship as the god of all doors, gates, and entrances. Some say Februarius got its name from a goatskin thong called a februa ("means of purification.") On the 15th day of this month Romans observed the festival of Lupercalia.

During the festival, a februa was wielded by priests who used it to beat women in the belief that it would make a barren woman fertile. However, there’s a Latin verb februare, meaning to "expiate" or "purify." It seems more reasonable to assume the purification people had in mind when naming the month was that of the calendar year’s length, not that of women upon whom the thong was applied. Februrary (at the end of the year) Apparently Februarius, when adopted, had but 23 days  traditionally the 23rd day of that month was the end of the calendar year. That indicates Februarius was observed in pre-Romulan times when months had as few as twenty days. Also, adding five days at year-end (to extend February’s length to 28) is similar to the change made by many other peoples who, around the time of Rome’s founding, added five days to their own calendar, but considered them to be unlucky and not part of the normal year. Why is our leap day in Februrary, not the end of the year?

Romans always reconciled differences between calendar and solar year lengths during the "Month of Purification." Whenever and however Roman calendars were modified to correspond to year length, it was always done after the 23rd day of February, traditionally the last day of the year. Even in our time, leap year is observed with a 29-day February. To purists, "leap day" is February 24, not the 29th. Plutarch wrote: "Numa...added an intercalary month, to follow February, consisting of twenty-two days, and called by the Romans the month Mercedinus. This amendment, however, itself, in course of time, came to need other amendments." (When observed, that leap month always immediately followed February 23.) According to historian Livy, Numa divided the year into twelve months, corresponding to the moon’s revolutions.

But as the moon does not complete thirty days in each month, and so there are fewer days in the lunar year than in that measured by the course of the sun, he interpolated intercalary months and so arranged them that every twentieth year the days should coincide with the same position of the sun as when they started, the whole twenty years being thus complete. He also established a distinction between the days on which legal business could be transacted and those on which it could not, because it would sometimes be advisable that there should be no business transacted with the people. Others claim that it wasn’t until 452 B.C.E. that a month named Intercalaris was added to the Roman calendar in order to add those days required to bring calendar length back into phase with the solar year. This month also began after the 23rd day of Februarius. It was observed every second year and was said to have had a length of either 22 or 23 days, with the remaining five days of Februarius added after them. Beware the Ides of March! SOOTHSAYER. He is a dreamer; let us leave him. Pass. [Sennet.

Exeunt all but BRUTUS and CASSIUS.] If you’ve heard the warning, "Beware the Ides of March," then it’s probably due to the works of William Shakespeare. The Roman ruler, Julius Caesar, was assassinated on the Ides of March - March 15, 44 B.C.E. In Shakespeare’s play Julius Caesar, (I, ii, 33), a soothsayer tells Caesar who is already on his way to the Senate (and his death), "Beware the Ides of March." Caesar asks him to come closer and repeat what he has just said. He studies the man’s face, listens to the warning again, but decIdes, "He is a dreamer, let us leave him. Pass." There is irony here, because the audience knows (from history) that Caesar will be killed on the Ides, and that he is exercising poor judgement in dismissing this prophecy.

Later, when he meets the Soothsayer again on the way to the Senate, he confidently says to him, "The Ides of March have come." But the Soothsayer reminds him, "Ay, Caesar, but not gone." There will be other warnings to Caesar from different people, which he will ignore, and go off to meet his death. The phrase "Beware the Ides of March" is one of the most remembered lines of Shakespeare’s plays. The unidentified soothsayer from Shakespeare’s play may have been a Roman astrologer by the name of Spurinna. According to to historical writer C.J.S. Thompson (and confirmed in Plutarch’s account of the story written in 75 C.E.) it was reportedly sometime prior to the fateful day of March 15 that Spurinna had first given Caesar the famous warning to "beware of the Ides of March." The astrologer, Spurinna, had previously warned Caesar that on the Ides of March, he would be in great danger. If, however, Julius Caesar took care on that one day - then all would be well.

According to Plutarch, Caesar had previously made the wise decision to stay within the safety of his bedroom chambers on the 15th of March. However, Caesar’s "friend" Decimus (Albinus) Brutus (not Marcus Brutus) managed to convince him that the astrologer’s warnings were nothing more than superstitious foolishness. So Julius Caesar decided to attend the Senate on the 15th of March. On his way to the Senate, Caesar "accidentally" met up with the astrologer, Spurinna. Caesar then told the astrologer "The Ides of March are come." Spurinna answered, "Yes, they are come, but they are not past." Later that day - on March 15, 44 B.C.E - Caesar’s enemies assassinated him in the Pompey theater, at the foot of Pompey’s statue, where the Roman Senate was meeting that day in the temple of Venus. Calendar a History - Timekeepers Calendar a History The origin of the first Calendar Who invented the Calendar A history of the Western Calendar Gregorian, Julian and Roman Calendars.

How the Days of the Week got their Names How the Months got their Names When was the Zero in use BC and AD Inventor Dionysius Exiguus. Timekeepingsite.org How they got their names The origin of the word Month . Zero between BC and AD? . Where did the number 60 seconds/minutes come from? 3500 BC to 2000 AD . The Calendar is a system for arranging the year into days, weeks and months. Lunar Calendar Historians donot know who or when mankind invented the first calendar, probably early man when he first carved a notch into a stick or a bone which marked the passing of each full moon. Notched bones used to record moon phases have been found in Africa and Europe dating back to about 20,500 BC. What is the Origin or Etymology of the word Calendar was the first day of each month in the ancient Roman calendar Middle English and Anglo-French calender .

Medieval Latin kalendarium, The Gregorian is the Calendar in use today Days of the Week How they got their names The Babylonians named each of the days after one of the planetary bodies known to them, a custom later adopted by the Romans, which continued with the The first day of the week, named for the Sun ..... Sun's-day For the History of the: Sabbath, Sunday and the First Day of the Week The second day of the week, named for the Moon ..... Moon's-day TUESDAY .... Mars's-day From the Roman warrior god Mars. Our culture adopted the Anglo-Saxon word for the warrior god of the Teutonic mythology Tiu or Tiw ..... Tiw's-day. From the Roman god of peace and prosperity. Our culture adopted the Teutonic god Wotan ..... Wotan's-day THURSDAY .... Jupiter's-day From the Roman god of lightning, thunder and the husband of Juno. Our culture adopted the Scandinavian god Thor, known as the thunder-god ..... Thor's-day FRIDAY .... Venus'-day Roman goddess of the spring seasons, Greek goddess of love. Our culture adopted the name Frigg, the Scandianavian goddess of Love ..... Frigg's-day.

From the planet of the same name. A Roman god of planting and harvest ..... Saturn's-day. How they got their names The word "month" is derived from the word "moon" French: "mois" - German: "Monat" Spanish: "mes" - Italian: "mese" - Latin: "mensis" Greek: "mén" or "mene" meaning moon JANUARY.... January was named for the Roman God Janus. God of doorways, entrances, gateways, thresholds and beginnings. He has two faces, looking in opposite directions. January was the eleventh month of the year in the ancient Roman calendar, however in the 2nd century BC it became the first month of the year. In the Middle Ages most European countries used the Julian calendar and observed New Year's Day on March 25. The Gregorian calendar came into use in 1582. Roman Catholic countries began to celebrate New Year's Day on January 1st at that time. However, Scotland didnot use the Gregorian calendar until 1600 and Germany, Denmark, and Sweden began in about 1700, England followed in 1752.

January now has 31 days FEBRUARY.... Named for the Roman festival of purification Februa. February dates from the time of Rome's founding and had 23 days and it was the last month of the year. In 452 BC February was placed in the second position of the Roman Calendar.with 29 days February now has 28 days or 29 in a leap year. MARCH.... Named for the Roman God Mars, who was the god of war and guardian of the state. Mars was the father of Romulus and Remus. In the Middle Ages most European countries used the Julian calendar and observed New Year's Day on March 25. March has 31 days. APRIL.... From the Roman calendar month of Aprilis. Considered a sacred month for the goddess Venus. April also comes from the Latin word aperire meaning "to open" refering to a spring season, opening of the flowers and leaves. April has 30 days. Named for the goddess Maia, the daughter of Atlas and one of the Pleiades. May has 31 days. Named for the goddess Juno, wife of Jupiter and queen of the heavens and gods.

June has 30 days. Named for Julius Caesar in 44 BC. The month originally had the Roman name of Quintilis. July has 31 days. Named for the Roman Emperor Augustus in 8 BC. The month was formerly known as Sextilis. August has 31 days. From the Latin word septem meaning seven, which was the seventh month of the Roman calendar September has 30 days. From the Latin word octo meaning eight, which was the eight month of the Roman calendar. October has 31 days. From the Latin word nove meaning nine, which was the nineth month of the Roman calendar. November has 30 days. From the Latin word decem meaning ten, which was the tenth month of the Roman calendar. December has 31 days. THE DAY The civil day in ancient cultures was made up of "Watches". The length of the watch varied with the season, and were called seasonal or temporal hours. They were related to the length of the Sun’s time above the horizon. This method was known as far back as 1800 BC and was used until the end of the 13th century AD in Europe.

At that time it became inconvenient to use because of the invention of the mechanical clock. The seasonal method was uneven and the mechanical clock had an even 12 hours for day and 12 hours for night. The 12 comes from Babylonian 2 x 12 = 24 (5 x 12 = 60). They did this rather than using the base 10. This is known as the Sumerian Sexagesimal System. as their day of rest and worship. (Mark 2:28) The gradual elevation of Sunday by Christians in place of the Sabbath was further enhanced by opposition to Judaism. The Emperor Constantine, who made his famous civil edict in A.D. 321 that men refrain from working on the first day of the week, Sunday is the "venerable day of the Sun," declared at the Council of Nicaea: "Let us, then, have nothing in common with the Jews, who are our adversaries.... " SUNDAY First day of the week in the USA In AD 321 Emperor Constantine established for the calendar a seven day week and Sunday as the First Day of the Week. Also that Sunday should be a day of rest and worship.

Sunday in Christianity is the "Lord’s day" which is a memorial to Jesus Christ’s Resurrection from the dead. Sunday worship dates back to the apostolic times. The author of Revelation writes: "I was in the Spirit of the Lords's day, and heard behind me a great voice, as of a trumpet," (Rev. 1:10) KJV MONDAY There are some countries which have Monday as the first day of the week. This is in accordance with the International Standard "ISO 8601:1988 (E)" 5.4 Combinations of date and time of day representations "A seven day period within a calendar year, starting on Monday and identified by the ordinal number within a year....." There are countries in Europe, such as Denmark, Norway and Sweden that have Monday as the first day of the week. In the USA documents ANSI (X3.30) and NIST (FIPS 4-1) adopted ISO 8601 and list Monday as the first day of the week. However, the calendar in USA has Sunday as the first day of the week. THE WEEK Known as an interval between Market Days.

In central Asia five days was used, Egyptians used ten days and the Babylonians like the multiple of seven because of the lunations of the moon. In Rome the eight day cycle was used for market. The origin of the seven day week seems to be related to the four (about) seven day phases of the moon. Also the seven colors in the rainbow, and in the Babylonian times, the seven planets. By the time of the first century BC the Jewish seven-day week seems to have been put into place throughout Rome. The calendar in the USA has Sunday as the first day of the week. The word week comes from Latin "vicis" meaning change. The week is a period of seven days and is now used throughout the world as a division of time. History seems to favor the Hebrew or Chaldean origin and the week is mentioned as a unit of time in the Bible, see the Old Testament book of Genesis 29:27. There are countries in Europe, such as Denmark, Norway and Sweden that have Monday as the first day of the week.

In the USA documents ANSI (X3.30) and NIST (FIPS 4-1) adopted ISO 8601 and list Monday as the first day of the week. THE MONTH The Month is taken from the cycles of the Moon phases, which takes about 29.5 days. The Babylonians used 29 and 30 days alternately. The Egyptians used all 30 day months, also the Greeks. The Romans made the Julian calendar on one 28 day month and the others either 30 or 31. January is the first month of the year in the Gregorian calendar with 31 days, and is named for the Roman god Janus, the god of gates, doors, openings and beginnings. January was the 11th month of the year in the ancient Roman calendar, however in the 2nd century BC it became the first month of the year. The month of March is the third month of the Gregorian year in accordance with our present calendar. However, March was the first month of the Roman year and named for Mars the god of war.

In England, until the Gregorian calendar was adopted in 1752, March was considered the first month with the legal year beginning on March 25. The month (which is lunar) is notsuitable for determining seasons, it has to be the Sun. The Month is determined in two ways. First, the period taken to complete one orbit of the Earth. Second, the time for the moon to complete a cycle of it phases, called the synodic month and is 29.53059 days, this is the basis of the calendar month. THE YEAR The year is the period for one orbit of the Earth around the Sun. And is measured at the Vernal Equinox (the spring-time) which equals about 365.2 mean solar days which is a tropical year (it varies). If the Synodic months (lunar) are used to count a year, 12 synodic months equal about 354.3 days. This is almost 11 days shorter than the tropical year. And if used it throws the seasons out of sync. Neither tropical (Sun) or synodic (Moon) has a complete number of days.

So to compile a calendar that keeps in step with the moon’s phases or with the Sun’s seasons it is necessary to insert days into the calendar which is called "Intercalations". Mean Sidereal time ( Star Time) is about 365.2 with reference to the Stars, one year has past. When the Earth has completed 365.2 rotations with reference to the Sun, one mean solar year has past. Mathematical tables are used to derive mean solar time from mean sidereal time. Neither mean solar nor mean sidereal time is precisely accurate, because the motion of the earth on its axis is not regular. Ephemeris time is used by astronomers for the greatest degree of accuracy. Ephemeris are tables giving the computed positions of celestial bodies for every day of a given period. It is an astronomical almanac containing positional tables. The base position is the vernal equinox. Through the use of mathematical tables, Ephemeris time is converted into mean solar time. Using mean sidereal time the year is: 365 days 6 hours 9 minutes 9.54 seconds.

Using mean solar time the year is: 365 days 6 hours 13 minutes 53.1 seconds. A tropical year is: 365 days 5 hours 48 minutes 46.3 seconds The rotation of the earth on its axis, and its tour around the sun, causes the times to vary from year to year, that is the reason for the leap second and the leap year.

Question: Which month of the Gregorian calendar was originally the first month of the Roman calendar?
Answer: March